1. Field of the Invention
The present invention relates to a structure for mounting a radiating plate which is provided on a semiconductor integrated circuit to be installed in a printed circuit board.
2. Description of Related Art
Semiconductor integrated circuits have recently come to be prepared to have a high degree of density. As a result, the heat build-up amount of flat-package-type semiconductor integrated circuits is trending upward. It has become difficult to sufficiently lower the temperature of these semiconductor integrated circuits by natural cooling. The semiconductor integrated circuits, however, must be cooled, because exposing them to high temperature tends to cause them to malfunction.
Known methods for cooling the flat-package-type semiconductor integrated circuits include air cooling by mounting a radiating plate (a heat sink), forcible cooling with a cooling fan, and cooling by Peltier effect attained with a Peltier element.
The methods of using a cooling fan or a Peltier element give an excellent cooling effect. However, these methods have necessitated securing a power source for operating the cooling fan or the Peltier element and also have incurred an inevitable increase in cost due to the addition of the cooling fan or the Peltier element.
The method of mounting a radiating plate permits cooling the semiconductor integrated circuit at a lower cost than the methods of using a cooling fan or a Peltier element. For mounting the radiating plate on the flat-package-type semiconductor integrated circuit, it has been practiced to secure the radiating plate to the semiconductor integrated circuit by bonding with an adhesive, a double-sided adhesive tape or the like.
However, in cases where a shake or a downfall happens to inflict an impact on the radiating plate which is bonded with an adhesive, the bonded part of radiating plate tends to peel off. In such a case, the radiating plate would part from the semiconductor integrated circuit, becoming incapable of fulfilling its cooling function.
The present invention is directed to the solution of the above-stated problem of the prior art. An object of the invention is, therefore, to provide a structure for mounting a radiating plate on a semiconductor integrated circuit in such a way as to ensure that the radiating plate is never caused to peel off by any impact inflicted thereon.
To attain the above object, in accordance with an aspect of the invention, there is provided a radiating-plate mounting structure, comprising, a printed circuit board, a semiconductor integrated circuit installed on the printed circuit board, a radiating plate provided on the semiconductor integrated circuit, and spring urging means for pressing and fixing the radiating plate onto the semiconductor integrated circuit.
The above and other objects and features of the invention will become apparent from the following detailed description of preferred embodiments taken in connection with the accompanying drawings.